1. Field of the Invention
This invention relates to a color video signal transmission from a video signal recording/reproducing apparatus such as a video tape recorder and a video disc player to a color television receiver for displaying a color video signal reproduced from a recording medium such a magnetic tape and an optical disc on a television screen.
2. Description of the Prior Art
The conventional video tape recorder (VTR) has a VIDEO OUTPUT terminal for outputting therefrom a composite video signal of base band in which luminance and carrier chrominance signals of a color video signal are frequency-multiplexed. The conventional television (TV) receiver has a VIDEO INPUT terminal for receiving thereat the composite video signal. To display a color video signal reproduced at the VTR from a magnetic tape on the CRT screen of the TV receiver, the VIDEO OUTPUT terminal of the VTR and the VIDEO INPUT terminal of the TV receiver are connected to each other with a connection cable.
More specifically, the conventional video signal recorder has a reproduced video signal processing circuit for processing a reproduced signal from a magnetic tape to obtain a luminance signal and a carrier chrominance signal, and a mixing circuit for mixing the luminance and carrier chrominance signals to obtain a composite video signal which is fed to the VIDEO OUTPUT terminal. The composite video signal is transmitted from the VIDEO OUTPUT terminal to the VIDEO INPUT terminal of the conventional TV receiver through the connection cable. The TV receiver has a separating circuit connected to the VIDEO INPUT terminal for separating the composite video signal into the luminance and carrier chrominance signals, and a video signal processing circuit for processing the separated luminance and carrier chrominance signals to obtain R, G, B color signals which are fed to the CRT to produce a color image on the CRT screen.
Since the TV receivers having the above-described configuration have been widely spread, other conventional video signal recorders than VTRs, such as video disc players, have the above-described configuration for the connection to the TV receivers.
However, the above-described conventional connection system between a video signal recorder and a TV receiver has the following problems:
(1) Since the luminance and carrier chrominance signals are frequency-multiplexed to obtain the composite video signal at the recorder side and the composite video signal is frequency-separated to recover the luminance and carrier chrominance signals at the TV receiver side, the circuits for the frequency-multiplexing and frequency-separation would cause waveform distortion of the transmitted signal due to variations of the characteristics of filters and amplifiers and cause circuit noises which interfere with the transmitted signal. Thus, the quality of the transmitted signal would be largely degraded.
(2) In the case of the NTSC system, since the luminance and carrier chrominance signals are frequency-multiplexed so as to be interleaved on frequency axis to each other, the luminance and chrominance signals would interfere with each other to cause the cross-color and cross-luminance noises which affect badly the quality of the displayed image.
(3) Since the frequency bands of the luminance and carrier chrominance signals in the transmitted composite video signal are standardized (e.g., 4.2 MHz for the luminance signal and 0.5 MHz for the carrier chrominance signal in the NTSC system), wider band luminance and carrier chrominance signals than the standardized band cannot be transmitted. Even if the reproduced luminance and carrier chrominance signals from the reproduced video signal processing circuit of the video signal recorder are wide band signals, which can provide a high quality image, such wide band signals must be limited in band to the standardized narrower band signals before frequency-multiplexed to the composite video signal. The band limited signals cannot provide the high quality image which could be provided by the original wide band signals.